[c-nsp] 7600 Linecard decisision

[Arie Vayner (avayner)]

PFC can do policing (actually it has some different policing options
over the regular policing in regular IOS), but it can't do shaping.
Queuing is done on the egress linecard.
 
Arie


________________________________

	From: Peter Basquiat [mailto:peter.basquiat at googlemail.com] 
	Sent: Saturday, May 05, 2007 21:33 PM
	To: Arie Vayner (avayner)
	Cc: cisco-nsp at puck.nether.net
	Subject: Re: [c-nsp] 7600 Linecard decisision
	
	
	Arie, thanks for your answer.
	
	When comparing this two different QoS models with each other,
where are the main differences?
	Are there real disadvantages compared to "normal" CBWFQ?
	I believe that I will never use all possible classes in CBWFQ.
It seems that PFC-QoS only supports 
	up to 8 queues, this would be enough for our purposes. 
	Per (Ethernet Subinterface/Frame-Relay VC)
Queueing/Shaping/Policing should be possible, i dont think
	that the PFC isnt able to do that, right?
	
	
	
	
	
	2007/5/5, Arie Vayner (avayner) <avayner at cisco.com>: 

		Peter,
		
		The main difference is that all the "native" LAN modules
on the 7600
		(meaning all the WS-X65/67 etc) can't actually support
the "normal"
		class-based QoS model, but use a different model. 
		You can read about it here:
	
http://www.cisco.com/univercd/cc/td/doc/product/lan/cat6000/122sx/swcg/q
		os.htm
		
		This has to do with the way the packets are being
handled inside the 
		device. For the native LAN modules, all QoS
functionality is done on the
		PFC, and it supports only the above QoS functionality.
		
		When using SIP modules (or older OSM/FlexWan modules),
the QoS
		functionality (as well as other things such as MPLS
features) are 
		enhanced by the fact that the SIP has extended
processing resources on
		the module and the software allows using this processing
power for
		features which are not available on the native LAN
modules. This
		explains the additional cost - the SIPs have much more
hardware on them 
		(such as processor, memory etc)
		
		I think you can find some interesting reading on the
SIPs here:
	
http://www.cisco.com/univercd/cc/td/doc/product/core/cis7600/76sipspa/si

		pspasw/index.htm
		
		Arie
		
		-----Original Message-----
		From: cisco-nsp-bounces at puck.nether.net
		[mailto: cisco-nsp-bounces at puck.nether.net
<mailto:cisco-nsp-bounces at puck.nether.net> ] On Behalf Of Peter Basquiat
		Sent: Saturday, May 05, 2007 19:09 PM
		To: cisco-nsp at puck.nether.net
		Subject: Re: [c-nsp] 7600 Linecard decisision 
		
		It's not really clear in which direction our QoS stuff
will expand. At
		the moment Iam thinking on typically class-based wfq on
core and edge.
		
		What are the differences regarding QoS on the
WS-X6582-2PA compared to 
		SIP400/SPA?
		
		Other question: talking about features, what's with the
WS-X67xx
		modules, are there other/more features available or do
they have only
		more bandwidth?
		
		SIP400+SPA is much more expensive, without knowledge
about the exact 
		advantages it's really
		hard to judge.
		
		
		>Peter,
		>
		>Going for the SIP/SPA combination would allow you more
features
		>especially
		with regards to QoS and VPN PE-CE support.
		>Can you expand a bit about what kind of core/access QoS
you require? 
		>
		>Arie
		_______________________________________________
		cisco-nsp mailing list  cisco-nsp at puck.nether.net
		https://puck.nether.net/mailman/listinfo/cisco-nsp
		archive at http://puck.nether.net/pipermail/cisco-nsp/